System for charging secondary batteries.



J. A. WOTTON. SYSTEM FOR CHARGING SECONDARY BATTERIES. APPLIOATION FILED AUG. 6, 1912.

Patented Apr. 15, 1915.

.pointer, but insulated from UNITED STATES PATENT orator.

JAMES A. WOT'ION, OF MONTCLAIR, NEW JERSEY, ASSIGNOR TO ELECTRIC PRODUCTS 00., OF CLEVELAND. OHIO, A CORPORATION OF GEORGIA.

SYSTEM FOR CHARGING SECONDARY BATTERIES.

Specification of Letters Patent.

Patented Apr. 15, 1913.

Original application filed May 6. 1909, Serial No. 494,265. Divided and this application filed August 6,

1912. Serial No. 713,615. i

To (17/ 40720). if may concern y lie it. known that I, Janos A. lVo'rToN, a citizen of the United States. residing at Montclair. in the county of Essex and State of New Jersey. have invented certain new and useful Improvements in Systems for Charging Secondary Batteries; and I do hereby (letate the following to be a full, clear. and exact description of the intention, such as will enable others skilled in the art 'to which it appcrtsns to make and use the for imprm'emcnts in systems for charging secondar batteries the sulnect matter herein being directed specifically to direct curie nt systcm..,while the genus and that species comprehending alternating current systems are presented in said co-pending applica- 'tion.

In the accompanying" drawing.-- l*igure 1 is a diagrammatical View of a system embodying the features of the present i'nncntion, the meter casing being indicated in section, and the operating parts in elevation. Fig. 2 is'ayertical, central section through the meter.

' Referring to the drawing by numerals, 1 indicates a casing of the volt meter. and 2- the field magnets thereof. The armature 3 is mounted on pivots 1-. suitably insulated. as at 5, 5, from the casing"; Secured to the armature 3 is the index pointer (3, the upper or longer end of which moves relative to the graduated scale 7 for indicatingvoltage, the armature beingwound in the manner of an ordinary volt meter. An outer spring 3. of the flat spiral type, is fixed at one end to the upper pivot :l. and at the other end is suitably conencted as to a bracket it fixed to and insulated from the casing 1. Spring 3 is tens-ioned to press the pointer 6 toward the ZQIO point'of the scale 7, and the said spring" is electrically connected with the casing 1. Pointer 3 is in turn electrically connected with. one end at the winding of armature 3,

and the other end of said vinding is similarly connected to an inner spring 3. similar in construction and arrangement to spring 3'. Spring 3" is connected with tl resistance 13 of the meter by conductor It conductor 17 is connected-to spring 3" and extends thence to one side of battery 42 which is made up of the secondary cells to be charged. The other side of the battery 42 is connected to conductor which extends to a source of current a direct current dynamo for instance. it branch conductor 44 leads from conductor at?) to the end of resistance 13 opposite that connected to conductor 13, whereby the meter 1 subject to the current of battery 42 and adapt ed to be influenced by the voltage of said battery.

A pointer 22) is pivoted within casing 1 to swing on the same axis as pointer t3, and has .its upper end extending above scale 7 similarly to pointer 6. The pointers 6 and '23 both extend below their pi vets, and.

pointer 23 is formed with an inwardly turned finger 2-1 adapted to at times haveits inner end contact with a contact block 24 formed on the lower end of pointer 6. The 'lront face of easing 1 is tormed'with' an arcuate slot 23" struck "from the axis of the pointers as a center. A set screw 23 extends loosely through the slot 2; and has a tl'treaded engagement: with pointer 23. Tlu' head of the set screw is outside the casing and of larger diameter than the width of the slot 23, whereby. in operation. the set screw may be loosened and the pointer 23 moved manually across the face of the scale 7 to the required extent. it unt'lerstood that. the discharge voltage of a secondary cell is approximately two volts. and the battery voltage will therefore representthe product of the number of cells in the battery times two. The voltage of a cell on reaching afully charged condition ranges from 2.50 to and therefore it the battery -12 is made ap -oi twenty cells. the maximum voltage when tnllucharged will be approximately fifty. lheretore, the oporator. in practice. will position the, pointer I j "A conductor 34 leads from the opposite y'side of dynamo 35 from the conductor 43 .and has electrical"communications through controlling apparatus hereinafter described with conductor 41 for supplying the charging current from the dynamo to the battery. Said controlling apparatus includes an electro-magnet 30, armature 31, and contact block 32, said armature having a contact point 33. Point 33 and block 32 are of a size and material such as carbon not to be injured by sparking, though the spark occurring at this point is inconsiderable. Armature 31 may be spring actuated in a direction from the magnet or may be gravity operated as preferred. One end of the winding of magnet 30 is connected by conductor 34-with the source of current supply 35. The other end of said winding is con-. nected by conductor 36 to block 32, said conductor 36 being branched, as at 37, to the armature 38 of an electro-magnet 39. A branch 40 of conductor 34 is adapted at times to be closed in circuit with armature 38 when magnet 39 is energized.

Conductor 44 is branched, as at 45, leading to oneend of the winding of magnet 39, the other end .of said winding being grounded on the casing of the meter, as by conductor 46. Conductor 41 is branched, as at 47, leading to the armature 31.

When the battery 42 is introduced into the charging circuit and the current turned on, contact 33 being in contact with block 32, having been moved manually or otherwise into such contact, the charging circuit will be as follows: from generator 35, through conductor 34, through winding of magnet 30, through conductor 36, block 32, contact 33, armature 31, and conductors 47 and 41 to battery, and from battery to generator through conductor 43. The volt meter 1, of course, responds to the battery voltage by reason of the battery circuit as follows: conductor 41, to spring 3' and pointer 6 to windingof armature 3, to spring 3", to resistance 13, and conductor 44, to conductor 43 and battery. The pointer 23 having been set at the desired maximum voltage of the battery, the charging current continues to flow until the battery voltage rises sufiiciently for bringing the pointers into substantial parallelism, whereupon the contacting of contact members 26 and 27 will divert the battery cur-rein; as follows: from battery through conductor 41, to spring 3, to pointer 6, to pointer 23, to the casing of volt meter 1, to conductor 46 to the winding of magnet 39, said winding being of low resistance relative to the resistance 13, and through branch conductor 45, to conductor 44 and conductor 43 back to battery. Current in this circuit actuates armature 38 and thus short clrcuits the generator current from magnet 30 as fol lows: from generator 35, through conductor 34, to branch'conductor 40, through armature 38, to branch conductor 37, directly to conductor 36, to block 32, through contact 33, to armature 31, to conductors 47 and 41, to battery, to conductor 43, back to the generator. This short cireuiting eliminating the magnet 30, allows the armature 31 to be drawn or fall away from the magnet and thus break contact between elements 32 and 33.

What I claim is: g

1. In a system of the class described, the combination with acharging circuit, and a battery to be charged interposed in said circuit, of a meter, a battery circuit for the meter for influencing the meter by battery current, a circuit breaker interposed in the charging circuit, an electro-magnet interposed in said charging circuit and disposed for retaining the circuit breaker closed during excitation of the charging circuit, a normally broken shunt across the electro -magnet for the charging circuit adapted when closed to" cut out the electro-magnet, an electro-magnet having its armature. inter- ,posed in the shunt and adapted to close the shunt when the last mentioned elect'ro-magnet is energized, and a circuit for the last mentioned electro-magn'et adapted to be closed by the meter under the influence of the battery circuit. v '2. In a system of the class described, the combination with a charging circuit, a meter connected to be influenced relative to condi- 00 tions of the charging circuit, a. circuit breaker interposed in the charging circuit, an electro-magnet controlling said circuit breaker .when energized, said electro-magnet being .connected to be energized by the 5 charging circuit, a shunt across the magnet adapted to remain normally open and t6 deenergized the magnet when closed, andmeans controlled by the meter for closing said shunt.

3. In a system of the class described, the combination with a circuit breaker controlling means therefor, battery charging circuit including said breaker and said controlling means, a branch circuit adapted for short 115 circuiting said controlling means, an elec fro-magnet for closing the branch circuit,

and battery voltage actuated means for energizing said'magnet.

4. In a systemof the class described, the combination of abatteny-charging circuit, a circuit breaker interposed therein, having an electro-magnet whose winding is also interposed in said circuit for retaining said circuit closed during charging operation, a branch circuit short circuited' about said magnet, an armature interposed in said branch circuit, an electro-magnet for actuating said armature, and battery circuit controlled means for energizing said magnet.

5. In a system of the class described, the combination with a charging circuit, a circuit breaker interposed therein, an electromagnet for maintaining said circuit breaker closed during the charging operation, the Winding of said magnet being interposed in the charging circuit, a branch circuit adapted for short circuiting the Winding of said electro-magnet, an armature interposed in said branch circuit and adapted to normally maintain the same open an electromagnet for actuating said armature for closing the branch circuit, a battery circuit for said electro-magnet, and battery voltage controlled means for closing said branch circuit.

6. In a system of the class described, the

combination with a charging circuit, of acircuit breaker therefor, an electro-magnet for actuating said circuit breaker, a normally open circuit for said electr0magnet, a movable contact, battery current influenced means for actuating the movable contact, and an adjustable contact in the path of inc tement of the movable contact and adapted ,to be engaged thereby for closing the magnet circuit.

In testimony whereof I afiix my signature in prcsenceot' t-Wo Witnesses.

JAMESA. VVOTTON. lVitnesses:

W. F. HOFFMAN,

MURRAY V. (.nmmv 

